Not knowing everything about cycling, can I ask, what is the benefit of moto pacing? Is it just to replicate being in the peloton, when training by yourself? It doesn't look like he's getting anything from it, apart from being dragged up the hill.
Motor pacing is used for a bunch of training techniques. It allows rider to maintain a high speed without breaking wind for themselves the entire ride. It also allows an interval technique of simply swinging out of the draft of the motor, you have to immediately increase your effort to maintain the speed of the moto. Another pretty common thing is to get up sprint faster , ahead of the moto and then after the effort, sit down and fall back behind the draft as the moto maintains a constant speed, to do any or all of those is difficult, to do them repeatedly while out on a motor paced ride takes real talent. With amateur racers you do a hard interval in front of the moto and as you come back to get the draft, you often get dropped if the moto maintains a constant speed.. You have to yell to slow down and allow you additional recovery and slowly regain speed. The best guys can chase the moto and recovery afterwards.. Really hard to do. Another thing that is fairly high risk is when elite riders are training at speed the moto will go ahead to try and stop or slow traffic so speeding rider can take corners or congested area at high speed. Also training using cars, motorcycles and scooters allows riders to use remote roads and vehicle will have water bottles, gels, spare wheels, flat repair items.. And riders can wear gloves, hats, warmers, shoe covers that can be removed as weather warms and you can give it to the vehicle to carry instead of putting it in jersey pockets or strapping it to the bike, creating a bunch of unwanted bulk. Riders like different calories depending on the day, so having different gels and different strength bottles is a nice option instead of stopping at the store or cafe.